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From: Markus Armbruster <armbru@redhat.com>
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Date: Tue, 27 Jan 2015 14:42:56 +0100
In-Reply-To: <54C78C24.2030304@redhat.com> (Paolo Bonzini's message of "Tue,
	27 Jan 2015 14:01:24 +0100")
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Subject: Re: [Qemu-devel] [PATCH] block: Simplify a few g_try_malloc() error
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To: Paolo Bonzini <pbonzini@redhat.com>
Cc: kwolf@redhat.com, qemu-devel@nongnu.org, stefanha@redhat.com

Paolo Bonzini <pbonzini@redhat.com> writes:

> On 27/01/2015 13:25, Markus Armbruster wrote:
>> Unlike malloc(), g_try_malloc() & friends return a null pointer only
>> on failure, never for a zero size.  Simplify tests for failure
>> accordingly.  This helps Coverity see returned null pointers can't be
>> dereferenced.  Also makes the code easier to read.
>
> Unfortunately that's not what I see from the source:
>
> gpointer
> g_try_malloc (gsize n_bytes)
> {
>   gpointer mem;
>
>   if (G_LIKELY (n_bytes))
>     mem = glib_mem_vtable.try_malloc (n_bytes);
>   else
>     mem = NULL;
>
>   TRACE (GLIB_MEM_ALLOC((void*) mem, (unsigned int) n_bytes, 0, 1));
>
>   return mem;
> }

You're right.  Brain fart, please ignore.